<?php
echo 12345,"\n";//十进制，可以用下划线分组
echo 012,"\n";//以0开头，后边是0-7，八进制
echo 0o12,"\n";//以0o开头，后边是0-7，八进制
echo 0b1101,"\n";//以0b开头，后边是0-1，二进制
echo 0x9A,"\n";//以0x开头，后边是0-9A-F，十六进制，字母不区分大小写

echo 8%5,"\n";//两个整数相除取余
echo intdiv(8,5),"\n";//只有整数部分
echo @(8.1%5.9),"\n";//两个整数相除取余,@()抑制警告信息
echo (int)8.1%(int)5.9,"\n";//两个整数相除取余,@()抑制警告信息
echo fmod(8.6,5),"\n";
echo 2**3,"\n";//2的3次方

echo 12+3.5,"\n";//转换为float进行计算
echo 1200+"12abc","\n";//12abc以数字开头，转换为12，结果1212
echo 1200+"3e4yy","\n";//3e4,3乘以10的4次方，转换为30000.结果31200
//echo 1200+"12abc","\n";//abc12不以数字开头，错误
//echo 1200+"","\n";""不以数字开头，错误
echo 1200+true,"\n"; //true转换为整数1，结果1201
echo false+1200,"\n";//false转换为整数0，结果1200
echo null+1200,"\n";//null转换为整数0
